细胞功能的光动力调控

Photodynamic modulation of cellular functions

光动力作用所产生的单线态氧分子因其有限的寿命(1μs)和有效反应距离(<10 nm),可亚细胞特异性调控细胞的不同生理活动。如质膜定位的光动力作用可导致胆囊收缩素(cholecystokinin,CCK)1型受体的永久性激活,及其它G蛋白耦联受体的增敏或脱敏。近年来涌现出来的基因编码的蛋白质光敏剂,使得光动力作用的亚细胞定位变得更加精细可控,因而可实现亚细胞部位及功能蛋白的靶向光动力调控。蛋白质光敏剂毒杀红(KillerRed)、迷你单(miniSOG)、单蛋敏(singlet oxygen protein photosensitiser,SOPP)等的亚细胞定位表达,可光动力调控细胞局部生理过程,通过对特定蛋白的光氧化活性改变,阐明该蛋白在细胞生理过程中的作用。选择性光照技术,可实现同步多点局部光照。多点局部光动力作用调控,可阐明细胞局部对整体细胞,及个体细胞对细胞团块的影响。蛋白质光敏剂的光动力作用,正逐渐成为细胞生理学研究的重要纳米调控工具。

Photodynamic action, due to the rather limited lifetime （1 μs） and effective reactive distance of singlet oxygen （〈 10 nm）, could subcellular-specifically regulate different cellular functions. Photodynamic action could activate permanently cholecystokinin （CCK） 1 receptors, and sensitize or desensitize other G protein-coupled receptors. The emergence in recent years of genetically- encoded protein photosensitisers has enabled more precisely-targeted photodynamic modulation of subcellular organelles and functional proteins. Protein photosensitisers （such as KillerRed, miniSOG or SOPP） expressed on the plasma membrane, mitochondria, lysosomes or endoplasmic reticulum can modulate photodynamically subcellular functions and fine-tune protein activity by targeted photooxidation. With the newly emerged active illumination technique, simultaneous photodynamic action localized at multiple sites is now possible, and the contribution of subcellular regions to the whole cell or individual cells to a cell cluster could be quantitated. Photodynamic action with protein photosensitiser will be a powerful tool for nano-manipulation in cell physiology research.